阅读说明：本技术 一种磁致伸缩材料性能测试装置及方法 (Magnetostrictive material performance testing device and method ) 是由 张洪平 牟星 程超 赵栋梁 祁焱 徐立红 郭世海 于 2020-08-06 设计创作，主要内容包括：本发明公开了一种磁致伸缩材料性能测试装置和方法,其中测试装置包括主体部件、第一扣件、第二扣件、励磁线圈、励磁线圈龙骨、磁感测量线圈、霍尔探头、电阻应变片、材料测试样件、螺纹锁紧压盖、T型加压杆、压力气体连接管或弹性元件。本发明采用环氧树脂将励磁线圈、磁感测量线圈、霍尔探头与励磁线圈龙骨固化成一体,通过螺纹连接、螺纹锁紧压盖将测试装置各部件固定在一起,形成稳定的结构。本发明的测试装置具有体积小、重量轻、一体化、结构稳定的特点,能够安装在振动试验台、冲击试验台上以及放置在温度试验箱中,测试磁致伸缩材料在振动、冲击、温度条件下磁化性能、磁致伸缩性能及温度稳定性。(The invention discloses a performance testing device and method for a magnetostrictive material, wherein the testing device comprises a main body part, a first fastener, a second fastener, an excitation coil keel, a magnetic induction measuring coil, a Hall probe, a resistance strain gauge, a material testing sample piece, a thread locking gland, a T-shaped pressurizing rod, a pressure gas connecting pipe or an elastic element. The invention adopts epoxy resin to solidify the excitation coil, the magnetic induction measuring coil, the Hall probe and the excitation coil keel into a whole, and all parts of the testing device are fixed together through threaded connection and a threaded locking gland to form a stable structure. The testing device has the characteristics of small volume, light weight, integration and stable structure, can be arranged on a vibration test bed and an impact test bed and placed in a temperature test box, and can be used for testing the magnetization performance, the magnetostriction performance and the temperature stability of the magnetostriction material under the conditions of vibration, impact and temperature.)

1. The utility model provides a magnetostrictive material magnetic property testing arrangement, includes excitation coil (2), excitation coil fossil fragments (3), magnetic induction measuring coil (4), hall probe (5) and resistance strain gauge (6), places material test appearance piece (7) at excitation coil fossil fragments (3) center, and material test appearance piece (7) surface, its characterized in that are pasted in resistance strain gauge (6):

the testing device (16) further comprises: a main body component (1) with a mounting base, a T-shaped pressurizing rod (9), a first fastener (11) and a second fastener (13);

the main body part (1) is a tubular cavity with an opening at the upper end, the cavity is divided into an upper part and a lower part by a thread locking gland (8) in the cavity, the upper part is connected with a first fastener (11), the lower part is used for accommodating a material test sample piece (7), a magnet exciting coil keel (3), a magnet exciting coil (2), a magnetic induction measuring coil (4) and a Hall probe (5), and the lower end face of the material test sample piece (7) is in end face contact with the inner bottom of the main body part (1); the first fastener (11) and the second fastener (13) are step-shaped circular truncated cone-shaped pieces with holes;

the main body part (1) is in detachable rigid connection with the first fastener and the second fastener as follows: the lower end of the first fastener (11) is connected with the upper part of the main body component (1), and the lower end of the second fastener (13) is connected with the upper end of the first fastener (11); a static seal is arranged between the first fastener (11) and the second fastener (13), and a cylindrical cavity (11-1) is formed between the first fastener (11) and the second fastener (13);

an elastic element (14) is arranged in the cylindrical cavity (11-1) and is used for applying pressure to the T-shaped pressurizing rod (9);

one end of the T-shaped pressurizing rod (9) is a circular table, the other end of the T-shaped pressurizing rod is a round rod, an annular groove is formed in the side surface of the circular table, the T-shaped pressurizing rod (9) is arranged in the cylindrical cavity (11-1), and a first sealing ring (10) arranged in the annular groove and the side wall of the cylindrical cavity (11-1) form sliding sealing; the round rod penetrates through the bottom surface of the lower end of the first fastener (11) and the locking cover (8) to be abutted against the upper end surface of the material testing sample piece (7);

the excitation coil (2), the magnetic induction measuring coil (4), the Hall probe (5) and the excitation coil keel (3) are solidified into a whole by epoxy resin;

the testing device is arranged on an impact test bed, a vibration test bed or in a temperature environment test box and is used for measuring the magnetic property, the magnetostrictive property and the temperature property of a material under the environments of impact, vibration and temperature.

2. The magnetostrictive material magnetic property test device according to claim 1, characterized in that: the lower part of the main body component (1) is a disc type base (1-2), the disc type base (1-2) is provided with symmetrically and uniformly distributed mounting holes (1-1) with the same distance with the center of the main body component, and the testing device (16) is fixed on a vibration test bed or an impact test bed through nuts and screws.

3. The magnetostrictive material magnetic property test device according to claim 1, characterized in that: the excitation coil (2) is wound on the outer side of the excitation coil keel (3), and the excitation coil (2) and the excitation coil keel (3) are solidified into a whole by epoxy resin; the magnetic induction measuring coil (4) and the Hall probe (5) are embedded and fixed on the inner side of the excitation coil keel (3), and the magnetic induction measuring coil (4), the Hall probe (5) and the excitation coil keel (3) are solidified into a whole by epoxy resin.

4. The magnetostrictive material magnetic property test device according to claim 1, characterized in that: the first fastener (11) is a circular truncated cone with steps, the center of the first fastener is a cylindrical cavity (11-1) with smooth side walls, the end with the large diameter is an upper end, the upper end is provided with a first fastener internal thread (11-3), and the top surface of the upper end is provided with an annular groove for placing a second sealing ring (12); the end with small diameter is the lower end, the lower end is provided with a first fastener external thread (11-2), the center of the bottom surface of the lower end is provided with a circular through hole, and the diameter of the through hole is smaller than that of the cylindrical cavity; the second fastener (13) is a circular truncated cone with steps, a concentric hole is formed in the center of the second fastener, the end with the small diameter is the lower end, the outer side of the lower end is provided with second fastener external threads (13-1), and the end with the large diameter is the upper end.

5. The magnetostrictive material magnetic property test device according to claim 1, characterized in that: the upper part of the main body component (1) is a tubular cavity with an opening at the upper end, the upper end of the inner side of the upper part is provided with main body component internal threads (1-5), and the side wall is provided with a magnet exciting coil wire leading-in through hole (1-3) and a test signal wire leading-in through hole (1-4).

6. The magnetostrictive material magnetic property test device according to claim 1, characterized in that: the thread locking gland (8) is a circular ring with a central through hole and outer threads, is in threaded connection with the main body part (1), and is used for fixing the excitation coil (2), the excitation coil keel (3), the magnetic induction measuring coil (4) and the Hall probe (5) in a lower cavity of the main body part (1) in an encapsulating manner to form a stable whole with the main body part (1).

7. The magnetostrictive material magnetic property test device according to claim 1, characterized in that: the second fastener (13) is in threaded connection with the first fastener (11), and the first fastener (11) is in threaded connection with the main body component (1), so that the second fastener (13), the first fastener (11) and the main body component (1) form a stable whole.

8. The magnetostrictive material magnetic property test device according to claim 1, characterized in that: the side surface of the round table of the T-shaped pressurizing rod is provided with an annular groove provided with a first sealing ring (10).

9. The magnetostrictive material magnetic property test device according to claim 1, characterized in that: the main body part (1), the thread locking gland (8) and the T-shaped pressurizing rod (9) are made of materials with good magnetic conductivity, and the materials are selected from one of electrician pure iron, iron-cobalt alloy, iron-nickel alloy and low-carbon steel.

10. The magnetostrictive material magnetic property test device according to claim 1, characterized in that: the elastic member (14) in the cylindrical cavity (11-1) applies pressure to the material test piece (7) through the T-shaped pressurizing bar (9).

11. The magnetostrictive material magnetic property test device according to claim 1, characterized in that: the compression deformation of the elastic element (14) is adjusted by adjusting the screw thread entering amount of the second fastener (13) and the first fastener (11) to adjust the pressure on the T-shaped pressurizing rod (9), and the pressure is applied to the material test sample piece (7), wherein the elastic element (14) is one of a belleville spring group and a spiral coil spring.

12. A test method using the apparatus for testing magnetic properties of magnetostrictive material according to claim 1, characterized in that: the method comprises the following steps:

1) the excitation coil (2), the magnetic induction measuring coil (4), the Hall probe (5) and the excitation coil keel (3) are solidified into a whole by adopting epoxy resin;

2) the excitation coil (2), the excitation coil keel (3), the magnetic induction measuring coil (4) and the Hall probe (5) are packaged and fixed in a cavity at the lower part of the main body part (1) by a thread locking gland (8);

3) placing a material testing sample piece (7) in the center of the excitation coil keel (3), and sticking a resistance strain gauge (6) on the surface of the material testing sample piece (7);

4) and (2) the main body part (1) is detachably and rigidly connected with the first fastener and the second fastener as follows: the first fastener (11) is in threaded connection with the main body component (1), and the second fastener (13) is in threaded connection with the first fastener (11), so that the main body component (1), the first fastener and the second fastener are connected into a stable whole through threads;

5) applying prestress to the material test sample piece (7) by applying force to the T-shaped pressurizing rod, wherein the force applying mode is that an elastic element pressurizes;

6) the testing device which fixes all the components as a stable whole is arranged on a vibration test bed and an impact test bed or placed in a temperature test box, and the magnetization performance, the magnetostriction performance and the temperature performance of the material testing sample piece (7) under the conditions of vibration, impact and temperature are measured.

13. Use of a device for testing the magnetic properties of magnetostrictive materials according to claim 1, characterized in that: the testing device is connected with a magnetizing power supply, a dynamic/static strain gauge, a gauss meter, a fluxmeter and a data acquisition computer and is used for testing the direct current magnetization performance, the alternating current magnetization performance and the magnetostriction performance of a magnetostriction material or a soft magnetic material.

14. Use according to claim 13, characterized in that: the magnetostrictive material comprises rare earth giant magnetostrictive material, iron gallium magnetostrictive material, iron aluminum magnetostrictive material and other materials with magnetostrictive effect.

Technical Field

The invention belongs to the field of magnetic measurement, and particularly relates to a device and a method for testing magnetic performance parameters of a magnetostrictive material in vibration, impact and temperature environments.

Background

Magnetostrictive materials belong to a magnetically functional material, or more closely to a soft magnetic material. The magnetostrictive material can be magnetized by an external magnetic field, so that the magnetization state in the material is changed to generate magnetic induction, the shape/size of the material is changed, after the external magnetic field is eliminated, the material is recovered, namely the magnetic induction is reduced, and the shape and size are recovered or approximately recovered to the state before magnetization, the change of the shape and size of the material caused by the change of the magnetization state of the material due to the magnetization of the external magnetic field is called magnetostrictive effect, and the change rate of the shape and size is called magnetostrictive coefficient. The value describing the magnetization state of a material after magnetization is referred to as the 'magnetization' or 'magnetic induction', which characterizes the magnetization state in which the material is located. The ratio of the magnetic induction intensity to the external magnetic field intensity is called the magnetic permeability of the material, the magnetic permeability is also a parameter representing the easy magnetization degree of the material, the larger the magnetic permeability is, the easier the material is to be magnetized, that is, the smaller the external magnetic field intensity required by the material to reach the same magnetization state is. In general, soft magnetic materials are very sensitive to stress or external force, and when the materials have internal stress or are subjected to external force, the magnetic permeability of the materials is greatly reduced, and the magnetization state of the materials is also changed. In addition, the magnetic properties of a magnetic material are temperature dependent, and change with temperature, and for magnetostrictive materials, the magnetostriction coefficient of the material changes with temperature. The magnetostrictive material is a stress sensitive and temperature sensitive material, and parameters of the material, such as magnetostrictive property, magnetization property and the like, are different due to different stress states and temperature environments of the material.

Typical magnetostrictive materials include rare earth terbium dysprosium iron giant magnetostrictive materials, iron gallium giant magnetostrictive materials, iron cobalt vanadium soft magnetic alloy (1J22 alloy) with high saturation magnetic induction strength and larger magnetostrictive coefficient, and other materials with magnetostrictive effect include iron aluminum magnetostrictive alloy, ferrite magnetostrictive materials and the like. The materials can generate magnetostrictive strain and force output phenomena under the action of an external magnetic field, and are important electromechanical conversion materials for driving devices and acoustic transducer devices. Wherein, the rare earth Tb-Dy-Fe giant magnetostrictive material and the iron-Ga giant magnetostrictive material have the maximum saturated magnetostrictive coefficients which respectively reach over 1800ppm and 340ppm, and the saturated magnetostrictive coefficients of other magnetostrictive materials are below 100 ppm. Magnetostrictive materials, whether used statically or dynamically, are subjected to alternating external forces from pre-stress, loading stress and vibrational shock, which are not controllable by random variations in the actual process. The vibration impact force is from the structural vibration of the magnetostrictive transducer when the magnetostrictive transducer works; secondly, the material generates stretching strain, and the stress change is caused by the change of the compression quantity of an elastic element in the pre-stress mechanism; and finally the impact force generated by the vibration impact from the working environment of the transducer. Therefore, when examining the performance of the magnetostrictive material, not only the parameters of the material under the fixed stress value need to be measured, but also the stability of the performance parameters of the material under the vibration impact stress needs to be measured, that is, the performance parameters and the parameter stability indexes of the material need to be tested under various impact and vibration environments, so as to provide reference data for the application and design of the material. Besides ferrite magnetostriction, other magnetostriction materials belong to alloy materials, the alloy materials have the characteristic of low resistivity, and under the drive of an alternating current or dynamic magnetic field, the temperature of the materials is increased due to eddy heat, so that the working temperature point of the materials is changed. In addition, the working temperature of the magnetostrictive material may also vary with the temperature of the working environment in which the device is applied. At present, the performance parameters of magnetostrictive materials are data measured at room temperature, and the magnetostrictive materials belong to temperature sensitive materials, the performance of the materials can change along with the temperature, and particularly, the phenomena of easy magnetization direction, magnetic order/disorder, ferromagnetic/paramagnetic transition and the like of the materials can occur due to the change of the magnetic structures of some materials along with the temperature, so that the performance of the materials is fundamentally changed. Therefore, when examining the performance of the magnetostrictive material, it is not enough to measure the magnetic performance of the material at room temperature, but it is necessary to measure the performance of the material at a temperature different from the room temperature, and it is necessary to measure the performance of the material at different temperatures in a simulated temperature environment, determine the temperature coefficient or temperature stability of the material, and provide parameters for the application and design of the material.

Chinese patent application No.201410251901.8 discloses a device and a method for testing the parameter characteristics of magnetostrictive materials, which relates to the separation of the pre-stress and the load force loaded on the magnetostrictive materials during the magnetostrictive material test, and adjusts the pre-stress and the load stress loaded on the magnetostrictive materials by adjusting the compression amount of a first adjusting nut and a second adjusting nut arranged in the testing device on two groups of disc spring elements respectively. The magnetostrictive coefficient of the material is measured by testing the displacement of the ejector rod by adopting a set of laser displacement measurement system, the ejector rod is connected with the tested magnetostrictive material, the magnetostrictive material is magnetized under the action of a magnetic field to generate axial dimension change, the ejector rod is pushed to displace, and the displacement of the ejector rod is equal to the magnetization deformation quantity of the material. The device is provided with three magnetizing coils, and the surface of the magnetostrictive material is provided with a Hall sensor and a detection coil, and the three magnetizing coils and the magnetostrictive material are not provided with a fixing mechanism, can vibrate along with vibration impact in a vibration impact environment, and cannot realize stable measurement. In addition, the laser displacement measuring device does not consider the vibration environment and the problem that the relative displacement between the laser probe and the ejector rod generated by vibration affects the measurement. In addition, in an impact vibration environment, the elastic element (a disc spring is adopted in the device) can generate stress change under the action of impact vibration, so that the prestress and the loading force loaded on the magnetostrictive material are changed, the stress of the magnetostrictive material is changed, and the requirement of the test condition for the stability of the preset stress of the material cannot be met. The invention application does not relate to the problem of temperature performance test of magnetostrictive materials.

The chinese invention patent ZL 201410257922.0(CN104062610B) discloses a device and a method for testing the magnetic properties of a magnetostrictive material, and relates to a device for testing the magnetic properties of a magnetostrictive material under different pre-stresses, or a device for testing the magnetic properties of a magnetostrictive material under different pre-stresses. The device adopts a frame structure, applies axial pressure to magnetostrictive materials through a hand-operated scissor jack, measures the pressure applied to the magnetostrictive materials through an upper weighing sensor and a lower weighing sensor in the frame, rotates an adjusting lead screw of the scissor jack, changes the height of the jack, and jacks the magnetostrictive materials through the limit change of the frame. The adjusting screw rod of the hand-operated scissor jack is low in control accuracy and does not have the function of accurately adjusting and controlling the lifting height of the scissor jack, so that the stress adjusting accuracy is low, and the control stress stabilizing capability is poor. Meanwhile, as a mechanical frame structure is adopted, in the test process, when the magnetization of the magnetostrictive material is axially elongated, the stress of the magnetostrictive material is increased due to the limitation of the frame structure, and when the demagnetization of the magnetostrictive material is axially shortened or the magnetization of the material with the negative magnetostrictive coefficient is shortened, the stress of the material is reduced, so that the mechanical frame structure and the stress application mode are difficult to obtain stable prestress. Meanwhile, the testing device adopts the split structure units which are limited and combined together through the frame, does not have a stable structure, and cannot be placed on a vibration impact table to carry out a test for testing the performance stability of the magnetostrictive material under the impact vibration.

The Chinese invention patent ZL 201310530487.X (CN103558569B) discloses a 'magnetostrictive material magnetic property tester', which comprises a main measuring part, a standard force sensor, a stress applying device and a permanent magnet, wherein the stress applying device consists of a top cover, an oil cylinder, an oil pool base, the upper end of the oil pool base and a screw rod which penetrates through the upper end of the oil pool base and is integrated with a hand wheel. And rotating the hand wheel, lifting the screw rod, limiting the mechanical position of the magnetostrictive rod, and pressurizing oil in the oil cylinder to lift the top cover to pressurize the magnetostrictive material. This stress applying device is characterized by a powder oil-pressure tablet press. The tester provided by the invention adopts a mechanical structure limiting mode and an oil pressure tablet press pressurizing mode to pressurize the magnetostrictive material to test the magnetic property of the material. Because the oil medium in the tablet press is incompressible and the hand wheel and the lifting screw are mechanically limited, the axial structure space distance of the magnetostrictive material is fixedly limited and can not be changed after pressure is applied, when the magnetization of the magnetostrictive material is extended or shortened, the deformation of the material is limited or the stress of the material is changed due to the deformation, and the test stability is influenced. In addition, the tester of the invention is a split structure, and all parts are not stably fixed together, so that the tester is not suitable for performing impact vibration tests on a vibration impact table, and meanwhile, a heavy powder oil pressure tablet press is not suitable for being installed on the vibration impact test table for performance tests of magnetostrictive materials. The adoption of the stress application structure of the oil press is not suitable for testing the temperature performance of the magnetostrictive material at high temperature, low temperature and wide temperature range due to the volume and hydraulic oil.

The Chinese patent application No.201810709773.5 discloses a device and a method for measuring giant magnetostrictive material, and aims to provide a device and a method for measuring giant magnetostrictive material, which can meet the stress requirement in the measuring process and simultaneously do not influence the uniformity of a magnetic field. The device is only used for measuring the magnetostriction coefficient of the magnetostrictive material under compressive stress, and does not have the function of measuring other magnetic properties of the material. The pressure loading in the device is characterized in that a pressure control unit controls a cylinder to pressurize or decompress, a connecting rod connected to a piston of the cylinder drives a first pressure rod and a second pressure rod to move up and down, the first pressure rod and the second pressure rod are arranged in parallel, one end of the first pressure rod is connected with the connecting rod, the other end of the first pressure rod is respectively abutted to steel balls in two grooves on a pressure block, the thick pressure block is placed above a tested magnetostrictive material, the pressure generated by the cylinder is applied to the pressure rod, and the pressure of the pressure rod is transmitted to the pressure block through the steel balls and then transmitted to the magnetostrictive material through the pressure block. The exciting magnetic field part of the measuring device consists of a frame-structured magnetic yoke, an upper pole head, a lower pole head, an upper pole coil (exciting coil) and a lower pole coil (exciting coil), and a direct current is input into the coils by a direct current exciting power supply to generate a static magnetic field. The test sample is placed on the lower pole head, the measurement plate is placed on the test sample, and the pressure block is placed on the measurement plate. The magnetostrictive material is axially deformed under the magnetization of a magnetic field, so that the measuring plate is displaced, the displacement of the measuring plate is measured by adopting a laser position finder, and the magnetostrictive coefficient of the magnetostrictive material is calculated. The prestress loading mechanism of the measuring device is complex and unstable, the magnet yoke of the frame structure is large in size and heavy in mass, fixed connection and matching required by an anti-impact vibration structure are not arranged among all the parts, and the laser measurement requires a very high vibration stability environment. Therefore, the testing device is not suitable for measuring the magnetic performance of the magnetostrictive material in an impact vibration environment and a temperature-changing environment.

Therefore, for the test of the magnetostrictive performance and the magnetization performance of the magnetostrictive material, particularly for the performance test of the magnetostrictive material sensitive to stress and temperature under the environments of vibration, impact and temperature, a test device and a test method which have the advantages of stable structure, small volume, light weight, movable installation and capability of meeting the test requirements of the magnetostrictive material on the test of the magnetostrictive performance, the magnetostrictive performance and the performance stability under the test conditions of impact, vibration and temperature are needed.

Disclosure of Invention

The invention aims to provide a device and a method for testing the magnetic property of a magnetostrictive material, which can measure the magnetization property, the magnetostrictive property and the temperature property stability of the material under the environment states of impact, vibration and temperature; the device has small volume, light weight, integration and stable structure, and can be arranged on a vibration test bed, an impact test bed or a temperature test box.

In order to achieve the above purpose, the present invention provides the following technical solutions:

the utility model provides a magnetostrictive material magnetic property testing arrangement, includes excitation coil 2, excitation coil fossil fragments 3, magnetic induction measuring coil 4, hall probe 5 and resistance strain gauge 6, places material test sample 7 at excitation coil fossil fragments 3 center, and resistance strain gauge 6 pastes on material test sample 7 surfaces, and this testing arrangement 16 still includes: a main body part 1 with a mounting base, a T-shaped pressurizing rod 9, a first fastener 11, a second fastener 13 and a pressure gas connecting pipe 13-2;

the main body part 1 is a tubular cavity with an opening at the upper end, the cavity is divided into an upper part and a lower part by a thread locking gland 8 in the cavity, the upper part is connected with a first fastener 11, the lower part is used for accommodating a material test sample piece 7, an excitation coil keel 3, an excitation coil 2, a magnetic induction measuring coil 4 and a Hall probe 5, and the lower end surface of the material test sample piece 7 is in end surface contact with the inner bottom of the main body part 1; the first fastener 11 and the second fastener 13 are step-shaped circular truncated cone-shaped pieces with holes;

the main body part 1 is connected with the first fastener and the second fastener in a detachable and rigid way as follows: the lower end of the first fastener 11 is connected with the upper part of the main body component 1, and the lower end of the second fastener 13 is connected with the upper end of the first fastener 11; a static seal is arranged between the first fastener 11 and the second fastener 13, and a cylindrical cavity 11-1 is formed between the first fastener 11 and the second fastener 13;

the cylindrical cavity 11-1 is filled with pressurized gas for applying pressure to the T-shaped pressurizing rod 9;

one end of the T-shaped pressurizing rod 9 is a circular table, the other end of the T-shaped pressurizing rod is a circular rod, an annular groove is formed in the side surface of the circular table, the T-shaped pressurizing rod 9 is arranged in the cylindrical cavity 11-1, and a first sealing ring 10 arranged in the annular groove and the side wall of the cylindrical cavity 11-1 form sliding sealing; the round rod penetrates through the bottom surface of the lower end of the first fastener 11 and the locking cover 8 to be abutted against the upper end surface of the material testing sample piece 7;

the excitation coil 2, the magnetic induction measuring coil 4, the Hall probe 5 and the excitation coil keel 3 are solidified into a whole by epoxy resin;

the testing device is arranged on an impact test bed, a vibration test bed or in a temperature environment test box and is used for measuring the magnetic property, the magnetostrictive property and the temperature property of a material under the environments of impact, vibration and temperature.

The lower part of the main body part 1 is a disc type base 1-2, four mounting holes 1-1 which are symmetrically and uniformly distributed and have the same distance with the center of the main body part are arranged on the disc type base 1-2, and a testing device 16 is fixed on a vibration test bed or an impact test bed through nuts and screws.

The excitation coil 2 is wound outside the excitation coil keel 3, and the excitation coil 2 and the excitation coil keel 3 are cured into a whole by epoxy resin; the magnetic induction measuring coil 4 and the Hall probe 5 are embedded and fixed on the inner side of the excitation coil keel 3, and the magnetic induction measuring coil 4, the Hall probe 5 and the excitation coil keel 3 are solidified into a whole by epoxy resin.

The first fastener 11 is a circular truncated cone with steps, the center of the first fastener is a cylindrical cavity 11-1 with a smooth side wall, the end with the large diameter is the upper end, the upper end is provided with a first fastener internal thread 11-3, and the top surface of the upper end is provided with an annular groove for placing a second sealing ring 12; the end with the small diameter is the lower end, the lower end is provided with a first fastener external thread 11-2, the center of the bottom surface of the lower end is provided with a circular through hole, and the diameter of the through hole is smaller than that of the cylindrical cavity; the second fastener 13 is a circular truncated cone with steps, the center of the second fastener is provided with a concentric hole, the end with the small diameter is the lower end, the outer side of the lower end is provided with a second fastener external thread 13-1, the end with the large diameter is the upper end, the center of the top surface of the upper end is provided with a pressure gas connecting pipe 13-2, and the lower end surface of the upper end is a sealing surface.

The upper part of the main body component 1 is a tubular cavity with an opening at the upper end, the upper end of the inner side of the upper part is provided with main body component internal threads 1-5, and the side wall is provided with excitation coil wire leading-in through holes 1-3 and test signal wire leading-in through holes 1-4.

The thread locking gland 8 is a circular ring with a central through hole and outer threads, is in threaded connection with the main body part 1, and is used for packaging and fixing the excitation coil 2, the excitation coil keel 3, the magnetic induction measuring coil 4 and the Hall probe 5 in a lower cavity of the main body part 1 to be fixed with the main body part 1 into a stable whole.

The second fastener 13 is connected with the first fastener 11 by screw threads, and the first fastener 11 is connected with the main body component 1 by screw threads, so that the second fastener 13, the first fastener 11 and the main body component 1 form a stable whole.

The side surface of the round table of the T-shaped pressurizing rod is provided with an annular groove provided with a first sealing ring 10.

The main body part 1, the thread locking gland 8 and the T-shaped pressurizing rod 9 are made of materials with good magnetic conductivity, and the materials are selected from one of electrician pure iron, iron-cobalt alloy, iron-nickel alloy and low-carbon steel.

The pressure gas connecting pipe 13-2 is connected with an external pressure regulating valve, a pressure tank or a high-pressure gas bottle, pressurized gas is injected into the cylindrical cavity 11-1, pressure is applied to the material testing sample piece 7 through the T-shaped pressurizing rod 9, and the pressure value applied to the testing sample piece is adjusted through the pressure regulating valve.

In the cylindrical cavity 11-1, a pressure gas is replaced by an elastic member 14, and the elastic member 14 applies a pressure to the material test piece 7 through the T-shaped pressurizing bar 9.

The compression deformation of the elastic element 14 is adjusted by adjusting the screw thread penetration amount of the second fastening piece 13 and the first fastening piece 11 to adjust the pressure on the T-shaped pressurizing rod 9, and the pressure is applied to the material test sample piece 7, wherein the elastic element 14 is one of a belleville spring group and a spiral coil spring.

A test method using the apparatus for testing magnetic properties of magnetostrictive material as described, the method comprising the steps of:

1) the excitation coil 2, the magnetic induction measuring coil 4, the Hall probe 5 and the excitation coil keel 3 are solidified into a whole by epoxy resin;

2) the excitation coil 2, the excitation coil keel 3, the magnetic induction measuring coil 4 and the Hall probe 5 are packaged and fixed in a cavity at the lower part of the main body component 1 by a thread locking gland 8;

3) placing a material testing sample 7 in the center of the excitation coil keel 3, and sticking a resistance strain gauge 6 on the surface of the material testing sample 7;

4) the main body part 1 is detachably and rigidly connected with the first fastener and the second fastener as follows: the first fastener 11 is in threaded connection with the main body component 1, and the second fastener 13 is in threaded connection with the first fastener 11, so that the main body component 1, the first fastener and the second fastener are connected into a stable whole through threads;

5) applying prestress to the material test sample 7 by applying force to the T-shaped pressurizing rod in a pressurizing mode of pressurizing gas or pressurizing by an elastic element;

6) the testing device which fixes all the components as a stable whole is arranged on a vibration test bed and an impact test bed or placed in a temperature test box, and the magnetization performance, the magnetostriction performance and the temperature performance of the material testing sample 7 under the conditions of vibration, impact and temperature are measured.

The testing device is connected with a magnetizing power supply, a dynamic/static strain gauge, a gauss meter, a fluxmeter and a data acquisition computer and is used for testing the direct current magnetization performance, the alternating current magnetization performance and the magnetostriction performance of a magnetostriction material or a soft magnetic material.

The magnetostrictive material comprises rare earth giant magnetostrictive material, iron gallium magnetostrictive material, iron aluminum magnetostrictive material and other materials with magnetostrictive effect.

Compared with the prior art, the invention has the beneficial effects that:

the magnetostrictive material testing device is light in weight, small in size, integrated and stable in structure, can be installed together with a vibration test bed, an impact test bed, a temperature test box and other testing devices, and tests on the magnetization performance, the magnetostrictive performance and the performance stability of the magnetostrictive material in vibration, impact and temperature environments are carried out.

The excitation coil, the magnetic induction measuring coil, the Hall probe and the coil keel of the device are solidified into a whole through epoxy resin glue, and are locked and fixed together with the main body part through the threaded connection and the threaded locking gland, so that relative displacement of each part in vibration and impact tests is avoided, and an impact test sample piece is also avoided.

And thirdly, providing a stress application structure for stabilizing the stress of the magnetostrictive material under vibration and impact, and testing the magnetostrictive and magnetization performances of the material under vibration and impact under stable prestress. The method adopts the pressure gas to prestress the magnetostrictive material through the T-shaped pressurizing rod, and utilizes the compressibility characteristic of the gas to stabilize the stress of the tested material in the vibration and impact processes, so that the prestress of the material test sample piece is not influenced by the vibration, the impact and the material magnetization deformation.

And fourthly, providing a stress application structure for the magnetostrictive material with unstable stress under vibration and impact, wherein an elastic element is adopted to apply prestress to the magnetostrictive material through a T-shaped pressurizing rod, the material stress changes under the vibration, the impact and the material magnetization deformation, and the magnetostrictive and magnetization performances under the vibration and the impact of the material are tested.

And fifthly, the device and the method have a light structure for applying prestress, can be installed in a temperature test box, and can test the magnetization and magnetostriction performance of the magnetostrictive material under different temperatures and prestress under the prestress loading condition.

The test device of the present invention has a number of important advantages. The testing device has the advantages that the weight is light, the size is small, all the components are tightly and fixedly connected with the testing sample piece to form a stable structure, the relative displacement of each component in vibration and impact tests is guaranteed, the situation of impacting the testing sample piece is avoided, the integrated mounting base is arranged, the integrated mounting base can be fixedly mounted with the environment testing devices such as a vibration testing stand, an impact testing stand and a temperature testing box, and the testing of the magnetization performance, the magnetostriction performance and the performance stability of the magnetostriction material under the environments of vibration, impact and temperature can be provided. Secondly, the gas pressurization structure of the device is simple, only one T-shaped pressurization rod with a sealing ring and one fastener with a tubular inner cavity are provided, the test sample piece is prestressed by externally injected pressure gas, and no complex and huge air pressure bag, pressurization air cylinder and pressurization mechanism are provided, so that the characteristics of simplicity, lightness and stable structure of the test device are ensured, and the performance test and test requirements of the material in the environments of impact, vibration and temperature can be well met. Thirdly, the device adopts the pressure gas to prestress the magnetostrictive material through the T-shaped pressurizing rod, utilizes the compressibility of the gas to stabilize the stress of the test material under impact and vibration, can ensure that the prestress of the material test sample piece is not influenced by the vibration, the impact acceleration and the material magnetization deformation, tests the magnetostrictive performance and the magnetization performance under the impact and the vibration of the material under the stable prestress, and is favorable for testing the authenticity, the stability and the reproducibility of data. Fourthly, the testing device of the invention can provide a portable structure with prestress application, can be arranged in a temperature test box, and can test the magnetization performance, the magnetostriction performance and the temperature coefficient of the magnetostrictive material under different temperatures and prestress under the prestress loading.

The testing device can be used for testing the magnetostrictive performance, the magnetization performance, the performance stability and the like of magnetostrictive materials including rare earth giant magnetostrictive materials, iron gallium magnetostrictive materials and other materials with magnetostrictive effects in vibration, impact and temperature environments, and can also be used for testing the magnetic performance of metal soft magnetic materials in vibration, impact, temperature and pressure environments.

Drawings

Fig. 1 is a schematic view of a first embodiment of the apparatus for testing performance of magnetostrictive material according to the present invention, which employs gas pressurization.

Fig. 2 is a schematic view of a second embodiment of the present invention, which employs an elastic element for pressurization.

Fig. 3 is a schematic structural diagram of a third embodiment of the present invention, which is a test apparatus mounted on an impact and vibration platform.

Fig. 4 is a schematic structural diagram of a fourth embodiment of the present invention, in which the testing device is installed in a temperature environment testing box.

Fig. 5 is a graph showing the change of the magnetostriction coefficient of a magnetostrictive material under impact and vibration in a third example of the present invention.

FIG. 6 is a graph showing the change of the magnetostriction coefficient of a magnetostrictive material in the high and low temperature ranges in a fourth embodiment of the present invention.

Fig. 7 is a fifth embodiment of the present invention, which tests the variation of magnetostriction coefficient with the magnetization field strength in the normal state (static state) at room temperature for magnetostrictive materials.

Fig. 8 is a fifth embodiment of the present invention, which tests the variation of permeability μ 33 of magnetostrictive material with the magnetization field strength at room temperature in the normal state (static state).

Reference numerals

1 main body part 2 excitation coil 3 keel

4 magnetic induction measuring coil 5 Hall probe 6 resistance strain gauge

7 material test sample 8 screw locking gland 9T type pressure rod

10 first seal ring 11 first fastener 12 second seal ring

13 second fastener 14 elastic element 15 heat insulation pad

16 testing device 17 temperature test box 18 impact and vibration platform

1-1 mounting hole 1-2 disc type base 1-5 main body part internal thread

1-3 magnet exciting coil power line leading-out through hole 1-4 measuring signal line leading-out through hole

11-1 cylindrical cavity 11-2 first fastener external thread 11-3 first fastener internal thread

13-1 second fastener external thread 13-2 pressure gas connecting pipe

Detailed Description

The drawings show preferred embodiments and methods of the invention for illustrative purposes only. In order to clearly illustrate the objects, technical solutions and advantages of the present invention, the following detailed description of the present invention is provided in conjunction with the detailed description and the application results. The description is intended to be illustrative, and not to limit the scope of the invention. Alternative embodiments of the structures and methods described in the following discussion will become apparent to those skilled in the art without departing from the principles of the invention.

EXAMPLE 1 pressurization with gas

Fig. 1 is a schematic structural diagram of a first embodiment of a device for testing the magnetic property of a magnetostrictive material according to the invention. As shown in fig. 1, the testing device of the embodiment includes a main body part 1 with a mounting base, an excitation coil 2, a keel 3, a magnetic induction measuring coil 4, a hall probe 5, a resistance strain gauge 6, a material testing sample 7, a screw locking gland 8, a T-shaped pressure rod 9, a first sealing ring 10, a first fastener 11, a second sealing ring 12, a second fastener 13, and a pressure gas connecting pipe 13-2.

The lower part of the main body component 1 is a disc type base 1-2, four mounting holes 1-1 are symmetrically and uniformly distributed on the disc type base 1-2, the upper part of the main body component 1 is a tubular column body with an opening at the upper end, internal threads 1-5 of the main body component are arranged at the upper end of the inner side of the tubular column body, and the side surface of the tubular column body is provided with a magnet exciting coil power line leading-out through hole 1-3 and a measuring signal line leading-out through hole 1-4; the excitation coil 2 that produces the magnetic field is convoluteed on excitation coil fossil fragments 3, and magnetic induction measuring coil 4 inlays to be fixed in excitation coil fossil fragments 3 inboard, and hall probe 5 inlays to be fixed in excitation coil fossil fragments 3 inboard, adopts epoxy to pour into excitation coil 2, magnetic induction measuring coil 4, hall probe 5 and excitation coil fossil fragments 3 into an organic whole fixedly. The center is a through hole, the side surface is provided with a threaded locking gland 8, the threaded locking gland is made of magnetic conductive materials such as electrician pure iron and is in threaded connection with the main body component 1, and the excitation coil keel 3 is locked and fixed in the main body component 1; the first fastener 11 is a truncated cone-shaped part with steps, the center is a cylindrical cavity 11-1 with smooth side wall, the end with large diameter is the upper end, the upper end is provided with a first fastener internal thread 11-3, the top surface of the upper end is provided with an annular groove for placing a sealing ring, the end with small diameter is the lower end, the lower end is provided with a first fastener external thread 11-2, the center of the bottom surface of the lower end is provided with a circular through hole, the diameter of the through hole is smaller than the diameter of the cylindrical cavity 11-1, the first fastener 11 is connected with the main body component internal thread 1-5 through the first fastener external thread 11-2, and the first fastener 11 and the main body component 1 are fixed together; the second fastener 13 is a truncated cone-shaped member with steps, the center of the second fastener 13 is provided with a concentric hole, the end with a small diameter is a lower end, the outer side of the lower end is provided with a second fastener external thread 13-1, the end with a large diameter is an upper end, the top surface of the upper end is provided with a pressure gas connecting pipe 13-2, the second fastener 13 is connected with a first fastener internal thread 11-3 at the upper end of the first fastener 11 through the second fastener external thread 13-1 at the lower end, a second sealing ring 12 in an annular sealing groove at the top surface of the upper end of the first fastener 11 and the lower end surface at the upper end of the second fastener 13 form a static seal, and the second fastener 13 is fixed with the main body part 1 through the first fastener 11; a T-shaped pressure rod 9 with one end being a circular table and the other end being a round rod, wherein the side surface of the circular table of the T-shaped pressure rod 9 is provided with an annular groove, the T-shaped pressure rod 9 is arranged in a first fastener 11, a first sealing ring 10 arranged in the annular groove is combined with the smooth side wall of a cylindrical cavity 11-1 to form sliding seal, the round rod of the T-shaped pressure rod 9 extends out of the first fastener 11 through a central circular hole on the bottom surface of the lower end of the first fastener 11 to be in contact with the upper end surface of the material testing sample piece 7, and prestress is applied to the material testing sample piece 7; the resistance strain gauge 6 is pasted on the surface of a material testing sample piece 7 according to a certain direction, the material testing sample piece 7 is arranged in the center of the excitation coil keel 3, the lower end face of the material testing sample piece is in end face contact with the inner bottom of the main body part 1, and the upper end face of the material testing sample piece is in end face contact with the lower end face of the T-shaped pressurizing rod 9. The method comprises the steps of pressurizing by using pressure gas, calculating the pressure of the pressurized gas according to the cross section size and the set pressure of the material test sample piece 7, adjusting the gas pressure, introducing the pressure gas into a cylindrical cavity 11-1 of a first fastener 11 through a pressure gas connecting pipe 13-2, and applying prestress to the material test sample piece 7 through a T-shaped pressurizing rod 9.

The device is connected with an external measuring instrument and a power supply, such as a dynamic/static strain gauge, a gaussmeter, a fluxmeter, a lock-in amplifier, a magnetizing power supply and the like, loads direct current, alternating current, direct current and alternating current to an excitation coil, generates a static magnetic field, an alternating magnetic field and a direct current bias and alternating magnetic field, and tests the direct current magnetic property, the alternating current magnetic property and the direct current bias alternating current magnetic property of a material, including the magnetizing property, the magnetostriction property and the like.

EXAMPLE 2 pressing with elastic elements

Fig. 2 is a schematic structural diagram of a second embodiment of the apparatus for testing magnetic properties of magnetostrictive material according to the invention. As shown in fig. 2, the testing device of the embodiment includes a main body part 1 with a mounting base, an excitation coil 2, an excitation coil keel 3, a magnetic induction measuring coil 4, a hall probe 5, a resistance strain gauge 6, a material testing sample 7, a screw locking gland 8, a T-shaped pressure bar 9, a first fastener 11, a second fastener 13, and an elastic element 14. The lower part of the main body part 1 is a disc type base 1-2, four symmetrically and uniformly distributed mounting holes 1-1 are formed in the base, the upper part of the base is a tubular column body with an opening at the upper end, internal threads 1-5 of the main body part are formed at the upper end of the inner side of the tubular column body, and a power line lead-out through hole 1-3 of an excitation coil and a lead-out through hole 1-4 of a measurement signal line are formed in the side surface of the tubular column body; the excitation coil 2 generating a magnetic field is wound on the excitation coil keel 3, the magnetic induction measuring coil 4 is embedded and fixed in the excitation coil keel 3, the Hall probe 5 is embedded and fixed in the excitation coil keel 3, and the excitation coil, the magnetic induction measuring coil, the Hall probe and the keel are poured and fixed into a whole by epoxy resin; the center is a through hole, the side surface is provided with a threaded locking gland 8, the threaded locking gland is made of magnetic conductive materials such as electrician pure iron and is in threaded connection with the main body component 1, and the excitation coil keel 3 is locked and fixed in the main body component 1; the first fastener 11 is a truncated cone-shaped part with steps, the center is a cylindrical cavity 11-1, the end with the large diameter is the upper end, the upper end is provided with a first fastener internal thread 11-3, the end with the small diameter is the lower end, the lower end is provided with a first fastener external thread 11-2, the center of the bottom surface of the lower end is provided with a circular through hole, the diameter of the through hole is smaller than that of the cylindrical cavity 11-1, the first fastener 11 is connected with a main body part internal thread 1-5 at the upper end of the main body part 1 through the first fastener external thread 11-2, and the first fastener 11 and the main body part 1 are fixed together; the second fastener 13 is a truncated cone-shaped member with steps, the end with a small diameter is a lower end, the outer side of the lower end is provided with a second fastener external thread 13-1, the end with a large diameter is an upper end, the second fastener 13 is connected with a first fastener internal thread 11-3 at the upper end of the first fastener 11 through the second fastener external thread 13-1 at the lower end, so that the second fastener 13, the first fastener 11 and the main body part 1 are fixed together; a T-shaped pressure rod 9 with a circular truncated cone at one end and a round rod at the other end, wherein the T-shaped pressure rod 9 is arranged in a first fastener 11, an elastic element 14 is arranged at the upper end of the T-shaped pressure rod 9, the elastic element 14 is a belleville spring set in the embodiment, the round rod of the T-shaped pressure rod 9 extends out of the first fastener 11 through a central circular hole at the bottom surface of the lower end of the first fastener 11 to be contacted with the upper end surface of the material test sample piece 7, and the compression amount of the elastic element 14 is adjusted by adjusting the depth of a thread of a second fastener 13 entering the first fastener 11, so that prestress is applied to the material test sample piece 7; the resistance strain gauge 6 is pasted on the surface of a material testing sample piece 7 according to a certain direction, the material testing sample piece 7 is arranged in the center of the excitation coil keel 3, the lower end face of the material testing sample piece is in end face contact with the inner bottom of the main body part 1, and the upper end face of the material testing sample piece is in end face contact with the lower end face of the T-shaped pressurizing rod 9. According to the cross section size of the material test sample 7 and the set pressure, the deformation and the pressure of the elastic element 14 are calculated, and the material test sample 7 is prestressed through the T-shaped pressurizing rod 9.

The device is connected with an external measuring instrument and a power supply, such as a dynamic/static strain gauge, a gaussmeter, a fluxmeter, a lock-in amplifier, a magnetizing power supply and the like, loads direct current, alternating current, direct current and alternating current to an excitation coil, generates a static magnetic field, an alternating magnetic field and a direct current bias and alternating magnetic field, and tests the direct current magnetic property, the alternating current magnetic property and the direct current bias alternating current magnetic property of a material, including the magnetizing property, the magnetostriction property and the like.

EXAMPLE 3 attachment of the test device to an impact, vibration test bench

Fig. 3 is a schematic structural diagram of a third embodiment of a device for testing the magnetic performance of a magnetostrictive material according to the invention. As shown in fig. 3, this embodiment is the test apparatus 16 of the present invention mounted on a shock and vibration test stand 18, which includes the test apparatus 16 and the shock and vibration test stand 18. The magnetostrictive material test sample 7 is placed in the testing device 16, the first fastener 11 is screwed into the body member 1, and the T-shaped pressurizing rod 9 with the first seal ring 10 mounted thereon is fitted into the first fastener 11. The second sealing ring 12 is placed in the sealing groove at the upper end of the first fastener 11, and then the second fastener 13 is screwed into the first fastener 11 until the second sealing ring 12 is pressed. The testing device 16 is fixedly arranged on the impact and vibration test bed 18 through the base mounting hole 1-1 of the main body part 1 by adopting a nut and a screw of M12. The pressure gas connection pipe 13-2 is connected to an external pressure gas tank or gas cylinder through a pressure regulating valve. The dc magnetizing power supply, the static strain gauge, the gauss meter, and the data acquisition computer are connected to the testing device 16. And determining the pressure value of the pressure gas according to the prestress value required by the test, adjusting the pressure regulating valve to the set pressure value, and opening the gas valve to communicate the pressure gas to apply prestress on the test sample piece. The prestress value of the magnetostrictive material test sample piece in the embodiment is 8MPa and is kept constant. The excitation coil 2 in the test apparatus 16 was subjected to a 4A dc current, the strain value of the magnetostrictive material was read, and the current was kept constant (i.e., the magnetization field was kept constant). And starting the vibration table according to a preset vibration and impact mode, and testing and recording strain values of the magnetostrictive material in vibration and impact states.

Fig. 5 is a result of a variation test of the magnetostrictive performance of the magnetostrictive material in an impact and vibration environment in example 3 using the testing apparatus of the present invention under a constant prestress and magnetization field, wherein the abscissa axis is the vibration and impact duration, and the ordinate axis is the magnetostrictive coefficient.

EXAMPLE 4 mounting of the test device in a test chamber in a temperature Environment

Fig. 4 is a schematic structural diagram of a fourth embodiment of the apparatus for testing magnetic properties of magnetostrictive material according to the invention. As shown in FIG. 4, this embodiment is that the testing device of the present invention is installed in a temperature environment test chamber, which includes a testing device 16, a heat insulating block 15, and a temperature environment test chamber 17. The magnetostrictive material test sample piece 7 is placed in a testing device 16, a first fastener 11 is screwed into a body part 1 through threads, a T-shaped pressurizing rod 9 and a disc spring group 14 are respectively placed in the first fastener 11, a second fastener 13 is screwed into the first fastener 11 through threads to compress the disc spring group 14, the compression amount of the disc spring group 14 is calculated according to the prestress value required by testing, and the screwing amount of the second fastener 13 into the first fastener 11 is determined, wherein the prestress of the embodiment is 6 MPa. The testing device 16 with the adjusted prestress is placed in a high-low temperature environment test box 17, in order to keep the temperature uniform, a heat insulation cushion block 15 is arranged in the temperature box, and the testing device 16 is placed on the heat insulation cushion block 15. The direct current magnetizing power supply, the static strain gauge, the gauss meter and the data acquisition computer are connected with the testing device 16 through the wiring port of the temperature box. The temperature of the test process is gradually increased from low temperature to high temperature. Firstly, the temperature of the test box is adjusted to 130K, after the temperature is stabilized, 3.2A direct current is loaded to the excitation coil 2 in the test device 16, the direct current is maintained, the data of the strain gauge is read, the temperature is gradually increased to the next test temperature point, and after the temperature is stabilized, the strain value is read.

Fig. 6 is a test result of the variation of the magnetostrictive coefficient with temperature of the magnetostrictive material test sample of example 4 under a constant magnetization field and constant prestress, in which the abscissa axis is temperature and the ordinate axis is the magnetostrictive coefficient.

Example 5-the apparatus tests magnetostrictive coefficient, permeability with magnetization field strength of magnetostrictive material in static state Variations of (2)

Fig. 7 and 8 are examples of the magnetostrictive coefficient and the magnetic permeability of the magnetostrictive material according to the magnetic property testing device of the magnetostrictive material in a normal state (static state). And testing the material sample piece with the prestress of 9MPa, and pressurizing by adopting pressure gas.

The description of the invention and the embodiment provides a magnetostrictive material performance testing device and a magnetostrictive material performance testing method. The foregoing discussion discloses and describes merely exemplary methods and embodiments of the present invention and is not intended to limit the described embodiments and modifications. It will be appreciated by those skilled in the art that the invention can be embodied in other specific forms without departing from the scope of the invention as defined by the appended claims.